Stieve H
Biologie II der Rheinisch-Westfälischen Technischen Hochschule, Aachen.
Naturwissenschaften. 1988 Jun;75(6):288-96. doi: 10.1007/BF00367319.
The mechanism of transduction of the light stimulus into an electrical response signal is described for visual cells of vertebrates and invertebrates. Absorption of a photon by a rhodopsin molecule in the photosensory membrane of the visual cell leads to a delayed, relatively large single-photon-evoked response, the elementary excitatory response. The rhodopsin molecule starts an enzyme cascade via a G-protein. This leads to a considerably amplified decrease (vertebrates), or increase (invertebrates) of a large number of intracellular messenger molecules. Binding of these messenger molecules causes the opening of the sodium-preferring ion channels in the plasma membrane. Our present knowledge of the molecular mechanisms involved is described.
本文描述了脊椎动物和无脊椎动物视觉细胞将光刺激转化为电响应信号的机制。视觉细胞光感膜中的视紫红质分子吸收一个光子后，会引发一个延迟的、相对较大的单光子诱发反应，即基本兴奋反应。视紫红质分子通过G蛋白启动一个酶级联反应。这导致大量细胞内信使分子大幅减少（脊椎动物）或增加（无脊椎动物）。这些信使分子的结合会导致质膜中偏好钠离子的离子通道打开。文中介绍了我们目前对所涉及分子机制的了解。
